Gem Testing Laboratory


National Gem and Jewellery Authority pioneers in gemstone testing and certification in Sri Lanka. During the last five decades of its operation it has gradually grown into the current status. So far, NGJA gemmolosts carried out their duties with uttermost dedication making use of the available facilities. Because of their expertise in identifying gemstones most decisions were quite accurate, hence, up to now there were no complains whatsoever. At present private gemological laboratories are mushrooming everywhere, yet, the gemstone certificates issued by National Gem and Jewellery Authority are still sought after by most people. Only a few gemstone laboratories around the world are owned by the respective governments and this laboratory too falls under the same category. As such, NGJA certificates are widely accepted by both local and overseas gem dealers.

During the initiation and within the last several decades NGJA had used only the conventional gemological instruments. Since, its initiation up to the present NGJA attracts highly competent professionally qualified gemologists, as such NGJA could maintain a very high standard.

From time to time, NGJA upgraded the quality of gemstone certificates in line with other reputed gemstone laboratories; incorporating security features such as bar codes, QR codes and holographic stickers. Furthermore, upgrading was done so that the authenticity of the certificates could be found with the aid of a mobile phone or a computer from anywhere around the world where internet facility is available.

NGJA made a bold decision to upgrade the gemstone laboratory by incurring a substantial amount of money. This includes competency and infrastructure development. As a part of the program two NGJA gemologists were enrolled for reputed foreign courses in gemology each year to upgrade the professional staff. In addition, the laboratory is in the process of obtaining ISO certification. Once it is done, it would be the only ISO certified gemstone laboratory in Sri Lanka. On the other hand, NGJA is in the process of procuring state-of-the-art modern analytical instruments that are capable of detecting slightest amounts of gemstone enhancements as well as the detection of all types of synthetic gemstones. At present, state-of-the- art highly advanced Raman Microprobe and one FTIR had already been installed and are in operation. These instruments safeguard the precision of the work carried out by the laboratory and ultimately promote the international recognition for NGJA gemstone certificates.  Once the laboratory is equipped with all the instruments that are expected to be procured within the next couple of months the laboratory would surely be recognized as a highly advanced world class gemological laboratory.

Gemological Instruments NGJA Laboratory

Gemological microscope, 10x loupe, refractometer, polariscope, prism spectroscope, diffraction grating spectroscope,
Chelsea color filter, dichroscope, specific gravity balance, daylight & UV lamps, radiation tester, digital refractometer,
neodymium magnet, diluted acid, immersion cells, fiber-optic light. These are basic instruments used in the establishing
the general gemological features of the gem in question.

Advanced Instruments

The following state-of-the-art instruments are used for detail analysis of gemstones. Only a limited number of labs around the world have access to these tools, each of which is present in the NGJA Gem Laboratory.

Raman Spectroscope

•Rapid identification of gemstones (loose, mounted and rough)
•Identification of enhancements
•Identification of opaque gemstones/synthetic/simulants
•Analyzing diamonds that have undergone High Pressure High Temperature treatment (HPHT)

Raman Spectroscope including Professor Hennry Hanni’s Raman database

Fourier Transform Infrared Spectrophotometer (FTIR)

•Distinguishing between synthetic and natural gemstones
•Identification of heated/unheated corundum stones
•Enhancement identification of specific gemstones such as jadeite-jade with polymer impregnation and emerald with oil or polymer impregnation

Fourier Transform Infrared Spectrophotometer (FTIR)

Energy Dispersive X-Ray Fluorescence Spectrometer (EDXRF)

•Distinguishing between synthetic and natural gemstones
•Analyzing quality enhancement methods of specific gemstones
•Find the composition of the gemstones

Energy Dispersive X-Ray Fluorescence Spectrometer (EDXRF)


Types of gem testing laboratory certificates

1. Gemstone brief report certificate
2. Gemstone report with the photo image
3. Photo gem identification report
4. Photo gem identification report with disclosure of heat/unheat
5. Descriptive certificate
6. Descriptive certificate with disclosure of heat/unheat

Charges for each certificates

Gem valuation initial charge – Rs 250.00

1. Memo normal certificate – Rs. 1250.00
2. Photo certificate normal – Rs. 4000.00
3. Photo certificate heated or not – Rs. 6000.00
4. Detailed  certificate normal – Rs. 2000.00
5. Detailed  certificate heated or not – Rs. 4000.00
6. Gemstone report with the photo image –
7. Memo Photo semi-precious stones – Rs. 1500.00
8. Memo Photo precious stones below 3 cts – Rs. 2000.00
9. Memo Photo precious stones above 3 cts – Rs. 4000.00
10.Memo Photo precious stones (Heat or Unheated) below 3 cts – Rs. 2000.00
11.Memo Photo precious (Heat or Unheated) above 3 cts – Rs. 6000.00

Documents required to get a certificate

National Identity Card or
Passport or
Driving License

Centers available except Colombo main laboratory for gem testing service